Adjustable hydraulic door closure

ABSTRACT

In a door closure of the type having hydraulic fluid within a cylinder slowing or dampening the rate of retraction of a spring powered piston-piston rod assembly, a final closing kick action wherein a series of enlargements in the cylinder wall disposed near the fully retracted position of the piston allow the hydraulic fluid suddenly to by-pass the piston as it nears such fully retracted position. The closing kick action is disengagable. Where the normal closing rate of the closure is adjustable by rotation of the hydraulic cylinder a lock mechanism prevents the cylinder from inadvertent rotation except when the lock is manually released.

United States Patent [191 Larson 3,708,826 1 Jan. 9, 1973 [54] ADJUSTABLE HYDRAULIC DOOR CLOSURE [75] Inventor: Donald A. Larson, Rice Lake, Wis.v

[22] Filed: Nov. 30, 1970 [21] Appl. No.: 93,525

[52] US. Cl ..l6/52, 16/66 [51] Int. Cl. ..E05f 3/10 [58] Field of Search ..l6/52, 56, 57, 51, 66; 188/285, 289, 320, 312-317 [56] References Cited UNITED STATES PATENTS 3,249,961 5/1966 Quinn ..16/66 3,064,303 11/1962 Gray et al ..l6/52 2,453,956 11/1948 Angel] ..l6/66 2,091,904 8/1937 Baumann ..l6/5l 2,741,793 4/1956 Norelius 1 6/52 3,078,499 2/1963 Gray et al ..l6/52 3,413,679 12/1968 Waldo ...l6/52 1,115,539 11/1914 1'10fer1e..... ..l6/66 Primary Examiner-James T. McCall Assistant Examiner-Peter A. Aschenbrenner Attorney-Stanley G. Delahunt [57] ABSTRACT In a door closure of the type having hydraulic fluid within a cylinder slowing or dampening the rate of retraction of a spring powered piston-piston rod assembly, a final closing kick action wherein a series of enlargements in the cylinder wall disposed near the fully retracted position of the piston allow the hydraulic fluid suddenly to by-pass the piston as it nears such fully retracted position. The closing kick action is disengagable. Where the normal closing rate of the closure is adjustable by rotation of the hydraulic cylinder a lock mechanism prevents the cylinder from inadvertent rotation except when the lock is manually released.

2 Claims, 6 Drawing Figures ADJUSTABLE HYDRAULIC DOOR CLOSURE The present invention relates to hydraulic door closures, and particularly concerns closures which are adjustable, by which the speed or rate at which the door is closed is controllable.

Hydraulic door closures have been known for a good many years. Such closures typically involve an elongate cylinder and piston-piston rod assembly mounted between the door and door jamb, with a coil spring disposed within the cylinder in such a manner as to urge the piston-piston rod from an extended position when the door is open to a withdrawn position, thus forcing the door closed. Hydraulic fluid is used as a dampening medium by which to slow, and render relatively uniform, the rate at which the spring would resoundingly slam the door shut, if unimpeded. Ordinarily, the device is constructed such that during movement of the piston within the cylinder as the door 1 is opened, the hydraulic fluid within the cylinder readily passes through or over the piston so as not to impede its travel and make the door difficult to open. As the door closes, however, the fluid is allowed only to seep or flow slowly through or over the piston, thus slowing or dampening the action of the coil spring. The rate of flow over or through the piston during its closing travel determines the extent to which the action of the spring is impeded and thus controls the rate at which the door closes.

In recent years, hydraulic closures have been marketed which are adjustable by inclusion of means to adjustably control the rate of flow of the hydraulic fluid across the piston during the closing operation. Ziegler et al. US. Pat. No. 2,996,754, granted Aug. 22, 1961, discloses the first such closure wherein the closing rate is adjusted merely by manually rotating the hydraulic cylinder. Due to friction between the piston and the inner cylinder wall, the piston rotates with the cylinder about the piston rod. The latter, being affixed at the opposite end ofthe closure, cannot rotate. The movement of the piston on the piston rod varies the size of an orifice through which hydraulic fluid passes during the closing operation. Upon rotation of the barrel in one direction, the orifice is enlarged and the door closes faster. By rotation of the barrel in the opposite direction, the orifice is restricted and the closing rate is slowed.

One disadvantage of the closure specifically described in the Ziegler et al. patent is the need to detach the cylinder from the door in order to adjust the closure. Others have thus advanced a variant of the Ziegler et al. concept by attachingthe cylinder to the door or jamb through an end plug which is so secured in the cylinder end that the cylinder can be rotated with respect to the plug, while maintaining a hydraulic fluidseal so that the device does not leak. In these variants the cylinder can thus be rotated and the piston turned therewith on the piston rod to adjust the fluid controlling orifice, without detaching the cylinder from the door. Such devices have the disadvantage, however, that the cylinder can be inadvertently rotated out of adjustment, e.g., through manipulation by a curious child or even by a persons leaning or rubbing up against the closure.

A further disadvantage of the hydraulic closures above described also resides, paradoxically, in the slow rate of closing action which the closure is designed to achieve. Thus as the door closes, it may not be moving fast enough to trip the door latch upon closing, especially if the door does not fit properly or is swollen due to moisture, etc. Also, in northern climes where the exterior door contains storm panels (instead of screens), pressure exerted by entrapped air during final stages of 4 closing may so counteract the action of the closure spring as to prevent latching. It is thus desirable that a hydraulic closure be provided wherein, as the door approaches the fully closed position, the closing speed is suddenly increased in a final kick to sharply latch the door. Yet the closing .kick must be sufficiently brief in duration and occur at exactly the right point in the travel of the door so as to prevent the door from slamming hard and thus defeating one of the fundamental purposes of the hydraulic closure. Desirably the end"kick" without need of tools can be readily and quickly disengaged where not needed such as where the door contains screen panels and properly fits in place.

My improved door closure provides a precisely timed disengageable closing kick by which the door, as it nears its fully closed position, is smartly latched in place without unduly slamming.

The present invention also provides an improvement on the adjustable hydraulic door closures of the type generally disclosed in Ziegler et al. US. Pat. No. 2,996,754, in that the cylinder can readily and simply be rotated by one knowing how to do it without need of temporarily detaching of the closure, and yet cannot be rotated inadvertently by the action of a child or one moving or leaning against it.

The manner in which the present invention attains the advantages above discussed will become apparent from the description of a specific illustrative embodiment of my invention, taken in conjunction with the accompanying drawing, in which like reference characters refer to corresponding parts in the several views,

and in which:

FIG. 1 is a plan view of a device of the present invention mounted for operation on a door;

FIG. 2 is an enlarged plan view, partially in section, of the one end of the device attached to the door in closed position with the closing kick engaged, and showing also the construction of the piston-piston rod assembly as well as the control linkage by which the cylinder can be rotated without detachment from the door;

FIG. 3 isa view similar to FIG. 2, but wherein the device is positioned on the door with the closure kick disengaged;

FIG. 4 is a cross-sectional view partially cut away taken through the cylinder of the closure along lines 4--4 of FIG. 3;

FIG. 5 is a sectional view of the rotational control linkage, taken along the lines 5-5 of FIG. 3; and

FIG. 6 is a sectional view of the closer unit of FIG. 3 taken at in relation to FIG. 3.

Referring now to the drawings, it is best first to describe the manner of general construction and operation of my door closure. A cylinder or barrel 10 is connected at its closed end llthrough a rotational control linkage 12 by pin 13 to door bracket 14 which is fastened to door 16 through screws 18. Emerging from the other end 19 of barrel 10 is piston rod 20 which is pivotally connected through pin 21 to jamb bracket 22 which in turn is fastened to door frame 24, e.g., by means of screws 26.

A conventional hold open washer 27 is positioned between cylinder and jamb bracket 22 by which the closure can temporarily be held in an extended or open position. The hold open washer has special utility in connection with the closure kick feature of my invention, as will appear.

The inner structure of the hydraulic closure mechanism is best seen from FIGS. 24, inclusive. Cylinder 10 contains a piston 28 having an annular boss 30 extending from one face 31 thereof. The piston and the boss are centrally bored and tapped to engage and mate with the threaded inner end 32 of piston rod 20.

As is well known in door closures, a coil spring 33 is disposed within barrel 10about the piston rod 20, with the spring ends bearing respectively against piston face 31 and the end of the barrel through which piston rod extends. The spring normally urges the door closure to a closed position with piston rod 20 withdrawn and piston 28 positioned adjacent closed end 11 of the cylinder.

The piston 28 contains four peripheral notches 34 (FIG. 4) symmetrically placed so as to impart to the piston a somewhat cruciform shape. An annular extension 36 juts from the inside face 37 of the piston (opposite face 31 from which boss 30 extends) for a short distance terminating in an oblong valve retention plate 38. As can be seen, the narrow dimension of the retention plate between the parallel sides is substantially less than the diameter of the piston 28 while in the major dimension the diametral distance between the arcuate ends is just'slightly less than the piston diameter.

Retained on the extension 36 in the annular groove defined between piston face 37 and retention plate 38 is a flexible rubber annular disc valve 40.

The diameter of the piston 28 is just slightly less than the inside diameter of cylinder 10 allowing movement of the piston back and forth along the length of the barrel. The diameter of the flexible disc valve just equals and preferably slightly exceeds the cylinder diameter enabling it to form a seal against the cylinder wall. It will thus be seen that as the piston travels in a direction toward the closed end 11 of the cylinder in response to the action of spring 33 in closing the door 16, the piston 28 forms a rigid backup for the disc valve, with the latter forming a seal against the wall of the barrel preventing the passage of hydraulic fluid around the periphery of the valve. Further, the pressure of the fluid on the disc valve seals it tightly against piston face 37 preventing leakage of fluid through the center of the annular disc valve 40 and around the edge of the piston.

As the door 16 is opened, piston rod 20 is extended, pulling piston 28 toward cylinder end 19. Pressure exerted by the hydraulic fluid during movement-of the piston causes the flexible valve 40 readily to bend about the parallel sides of the retention plate 38 where unsupported thereby. Hydraulic fluid thus readily flows through the gap between the periphery of the piston and cylinder wall, and especially through the notches 34 in the piston. Hence, the hydraulic fluid offers little resistance to opening of the door.

The threaded end 32 of piston rod 20 is provided with an axial tapered groove 44, which reaches its maximum depth at the extreme end of the piston rod. The

length of the groove is less than the length of the I threaded portion 32. Thus, an adjustable orifice is defined between the threaded end of the piston rod and the tapped bore in piston 28 and boss 30, the size of the orifice depending upon the extent to which the piston is turned on the piston rod. As the door closes in response to the force of spring 33 on piston 28, hydraulic fluid will flow through said orifice; and the extent to which the action of the spring is slowed by the fluid depends upon the rate of flow permitted by the size of the orifice.

Adjacent the closed end 11, cylinder 10 is provided with several short axially extending spaced dimples 48. As can be seen, especially in FIGS. 2 4, the dimples appear as protrusions when viewed from the exterior of barrel 10 and as depressions when viewed from the interior. Hence, the inside diameter of the barrel is enlarged at the point of the dimples, with the increased diameter exceeding the diameter of the disc valve 40. As piston 28 approaches the closed position during closing of door 16, its speed is regulated by the flow of hydraulic fluid through the orifice defined by groove 44 in piston rod 20, as above described. However, when the piston reaches the position of the dimples 48, hydraulic fluid rushes also through the area defined by the dimples about the periphery of the disc valve 40 causing the door rapidly to kick shut.

I have found that several narrow dimples, e.g., six in the device herein described, are preferable to a fewer number of wider and deeper dimples. Wider dimples tend to allow the valve more readily to expand or extrude to fill the area of the dimples (impeding the desired fluid bypass), which does not occur with narrower dimples. On the other hand, deepening of the dimples may result in metal fracture in formation of the cylinder during drawing, or in pinching of the valve on the opening stroke as the door is opened.

End plug extension 49 is provided with outer and inner holes 50 and 52, respectively, by which the closed end 11 of cylinder 10 is fastened to door bracket 14 through removable pin 13. As will now be shown, whether the kick" mechanism is engaged or disengaged is governed by whether pin 13 extends through hole 50 or hole 52 in the end plug extension, and the device is quickly converted from one mode to the other by interchanging the position of the pin.

In the position shown in FIG. 2, connecting pin 13 extends through outer hole 50 in extension 49. In this position, the cylinder is moved toward the door jamb, relative to the piston, so that the full travel of the piston 28 within the barrel 10 carries it into the area of dimples 48. In this position, the closing kick at the end of the piston travel is operative. 0n the other hand, in the position shown in FIG. 3, the pin 13 connecting the door bracket 14 to the cylinder extends through inner hole 52 in plug extension 49, the barrel being displaced away from the door jamb relative to the position as shown in FIG. 2. Thus the full travel of piston 28 within the barrel during the closing operation does not carry far enough to reach the area of dimples 48. In this alternative position, the door kick is rendered inoperative.

lt will be observed that a relation exists between the length of dimples 48 and the distance between holes 50 and 52 in extension 49. The spacing of holes 50 and 52 must thus be at least great enough to permit piston 28 in the fully closed position to lie in the area of dimples 48 when (in relation to the position of door bracket 14 and door 16) pin 13 extends through hole 50, while precluding the piston from reaching the area of the dimples when the pin is in hole 52.

The kick mechanism in my novel disclosure is readily engaged or disengaged without need of any tools. Thus to change from the engaged position of FIG. 2 to the disengaged position of FIG. 3, as for example when one changes storm panels to screens in the spring of the year, one merely partially opens the door and sets the hold open washer 27 temporarily to hold piston rod 20 partially extended. This relieves the spring pressure on pin 13 across door bracket 14 and plug extension 49 so that the pin can easily be removed from hole 50. The door is then closed slightly to bring hole 52 into line with the corresponding hole in door bracket 14 and the pin reinserted to extend through hole 52. Hold open washer 27 is then released in the conventional manner, the kick" thus being disengaged. It can be re-engaged when needed, e.g., in the fall of the year when storm panels are again placedin the door, by again setting the cylinder in a partially extended position and changing the pin 13 from hole 52 to hole 50.

The closing rate of my improved door closure during the main part of the closing operation is controlled by rotating the cylinder in relation to door 16 through rotational control linkage 12. As shown in FIGS. 5 and 6, the linkage is comprised of plug 54 in the end 11 of cylinder and the aforementioned extension 49 which upon release of associated locking means rotate with respect to one another. The plug 54 is provided with a peripheral annular groove 55 in which is disposed O-ring 56 by which a tight seal is maintained when the end of the barrel is swaged about the plug. Exterior ridge 58 on plug 54 defines another annular groove exteriorly ofO-ring 56 into which the end edge of the barrel is pressed during the swaging operation. Thereby the end plug is permanently and securely held in place, and can be neither pushed into nor pulled from the barrel.

The outer end of plug 54 is provided with an axial bore 60 which communicates interiorly of the plug with a larger cylindrical chamber 62, shoulder 63 being defined at the point where the chamber and the bore meet. Extension 49 having inner head 66 is rotatably disposed within the bore 60 with the head positioned in chamber 62 and bearing against shoulder 63. The outer end of extension 49 is provided with outer and inner holes 50 and 52 respectively by which the end-linkage 12 is connected to door bracket 14 as above described.

The fabrication and assembly of plug 54 and extension 49 is facilitated by boring into the outer end of plug 54 to define bore 60 and then boring a larger hole from the inner end of the plug, this hole or bore having the diameter of chamber 62, the two bores meeting so as to define shoulder 63. Then an inner cap 68 is pressfit into place in the inner end of the larger bore so as to define the chamber 62,.it being importantthat a tight seal be provided between the press-fit cap and the plug,

so that hydraulic fluid does not leak therefrom.

Extension 49 15 provided with an axial groove into which movably sits lock button 70. Said button is urged radially outwardly from the extension by spring 72 positioned in a depression below the button. Button 70 and spring 72 are so positioned that the button extends under, but protrudes from, the outer end of plug 54. The plug, at its outer end, is provided with four radial notches 74 extending along bore 60 which receive button 70 when the rotational position of extension 49 is such that the button is disposed opposite one of the notches, When in this position, spring 72 urges the button into the notch securely locking extension 49 into place in relation to the cylinder 10. The barrel thus cannot be rotated and the closure speed of the mechanism thrown out of adjustment by an inadvertent rotation of the barrel. However, when-the button 70 is depressed so as to be freed of the notch 74 in which situated, the cylinder can readily be turned and the closure speed adjusted. Other rotation control means by which the extension 49 can be rotated in relation to the end of cylinder 10 can, of course, be visualized.

What I claim is:

1. In combination with a door closure of the type wherein the rate of close is adjustedthrough rotation of the closure mechanism thereof, a rotational control linkage between said closure mechanism and a doormounting bracket, said control linkage comprising an end member on said closure mechanism having at least one notch therein, an extension for connecting to said mounting bracket freely and rotatably attached to said end member, and a depressable lock button disposed in said end member for engaging said notch as the latter reaches the position opposite said lock button during rotation of the extension, spring means urging said button, unless depressed, into said engagement to prevent further rotation of the closure mechanism.

2. A hydraulic door closure having a final closing kick wherein the closing rate increases substantially near the fully closed position, said closure comprising a cylinder and piston-piston rod assembly, a spring within said cylinder urging said piston and piston rod to a retracted position, hydraulic fluid within said cylinder for slowingthe rate at which said piston and piston rod retract in response to the action of said spring means, at least one depression in the interior wall of said cylinder, said depression having an axial length greater'than. that of the peripheral portion of said piston and being disposed along the line of travel but closely adjacent the closed position of said piston, said depression allowing said hydraulic fluid suddenly and rapidly to by pass said piston substantially freeing the piston from the slowing action of said fluid; said cylinder being provided with a door-mounting bracket and means for connecting said bracket to said cylinder in a first position and a second position so that when said closure is fastened in position between a door and door jamb with said bracket and cylinder connected insaid first position the retracted position of said piston is opposite said depression, and when said bracket is connected in said second position the piston in retracting does'not reach the said depression. 

1. In combination with a door closure of the type wherein the rate of close is adjusted through rotation of the closure mechanism thereof, a rotational control linkage between said closure mechanism and a door-mounting bracket, said control linkage comprising an end member on said closure mechanism having at least one notch therein, an extension for connecting to said mounting bracket freely and rotatably attached to said end member, and a depressable lock button disposed in said end member for engaging said notch as the latteR reaches the position opposite said lock button during rotation of the extension, spring means urging said button, unless depressed, into said engagement to prevent further rotation of the closure mechanism.
 2. A hydraulic door closure having a final closing kick wherein the closing rate increases substantially near the fully closed position, said closure comprising a cylinder and piston-piston rod assembly, a spring within said cylinder urging said piston and piston rod to a retracted position, hydraulic fluid within said cylinder for slowing the rate at which said piston and piston rod retract in response to the action of said spring means, at least one depression in the interior wall of said cylinder, said depression having an axial length greater than that of the peripheral portion of said piston and being disposed along the line of travel but closely adjacent the closed position of said piston, said depression allowing said hydraulic fluid suddenly and rapidly to by-pass said piston substantially freeing the piston from the slowing action of said fluid; said cylinder being provided with a door-mounting bracket and means for connecting said bracket to said cylinder in a first position and a second position so that when said closure is fastened in position between a door and door jamb with said bracket and cylinder connected in said first position the retracted position of said piston is opposite said depression, and when said bracket is connected in said second position the piston in retracting does not reach the said depression. 